Abstract:In order to construct extendable, configurable and controllable state model, a constructive pattern for state reflection is proposed in this paper. Based on the reflective pattern of software architecture and role object pattern, the reflection approach for structure and behavior in the pattern of state design is discussed. At meta level and base level, the object structures for architecture of reflective pattern are designed. The relationship between the meta level and the base level is presented with the protocol of MOP (meta object protocol). The mechanism of interception and reification for object reflections from the meta level to the base level is discussed in the pattern of state reflection. Finally, an example of voucher using the pattern of state reflection is given in this paper.